Deer Park, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 16.6 °C (low) to 25.9 °C (high). Annual precipitation averages 1482.1 Millimeters. Deer Park is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.2 °C | 17.2 °C | 113.54 mm |
| February | 9.2 °C | 19.1 °C | 85.34 mm |
| March | 12.9 °C | 22.1 °C | 94.23 mm |
| April | 16.4 °C | 25.4 °C | 107.95 mm |
| May | 20.6 °C | 29 °C | 139.7 mm |
| June | 23.9 °C | 32.1 °C | 155.19 mm |
| July | 24.8 °C | 33.2 °C | 116.84 mm |
| August | 24.7 °C | 33.6 °C | 155.96 mm |
| September | 22.4 °C | 31.3 °C | 147.57 mm |
| October | 17.3 °C | 27.3 °C | 132.59 mm |
| November | 11.8 °C | 21.9 °C | 119.38 mm |
| December | 8.2 °C | 18.2 °C | 113.79 mm |
| Annual | 16.6 °C | 25.9 °C | 1482.08 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |